重置PDO结果中的数组指针

问题描述

我无法从MySQL SELECT方法转换为PDO方法.我想遍历两次提取的数组，两次都从零行开始.在MySQL中，我将使用:

I'm having trouble moving from MySQL SELECT methods to PDO methods. I want to iterate through a fetched array twice, both times starting with row zero. In MySQL I would use:

mysql_data_seek($result,0);

使用PDO方法，我不确定如何完成同一件事.下面的代码是我如何尝试执行此操作.第一个while循环可以正常工作，但是第二个while循环不返回任何内容.

Using PDO methods, I'm not sure how to accomplish the same thing. The code below is how I am trying to do this. The first while loop works fine but the second while loop returns nothing.

$pdo = new PDO('mysql:host=' . $host . ';dbname='.$database, $username, $password);
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$stmt = $pdo->prepare('SELECT * FROM mytable WHERE active = 1 ORDER BY name ASC');
$stmt->setFetchMode(PDO::FETCH_ASSOC);
$stmt->execute();

while($row = $stmt->fetch())
{
    //do something starting with row[0]
}
while($row = $stmt->fetch())
{
    //do something else starting with row[0]
}

推荐答案

将结果保存到数组中，然后将该数组循环两次.

Save your results to an array and then loop that array twice.

$pdo = new PDO('mysql:host=' . $host . ';dbname='.$database, $username, $password);
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

$stmt = $pdo->prepare('SELECT * FROM mytable WHERE active = 1 ORDER BY name ASC');
$stmt->setFetchMode(PDO::FETCH_ASSOC);
$stmt->execute();

$rows = $stmt->fetchAll();

foreach ($rows as $r) {
    // first run
}

foreach ($rows as $r) {
    // seconds run
}

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